Who Cursed Tulsi?

Later, Shiva killed Shankachuda with his trident. Vishnu appeared in his true form and urged Tulasi to abandon her earthly body and return to his celestial abode. In her anger and grief, she cursed Vishnu to be turned into stone.

What did Vishnu do to Tulsi?

Vrinda then drowned herself in the ocean, and the gods (or Vishnu himself) transferred her soul to a plant, which was henceforth called Tulsi. As per a blessing by Vishnu to marry Vrinda in her next birth, Vishnu – in form of Shaligram - married Tulsi on Prabodhini Ekadashi.

What is the story of Tulasi?

An enraged Tulasi devi cursed Lord Vishnu for His stone-hearted behaviour to become a stone. Lord Vishnu accepted this curse and promised to appear as the Saligrama shila in the Gandika river (now in Nepal). He also gave Tulsai devi the benediction that she will eternally reside with Him as His consort in Vaikuntha.